Re: [PATCH 21/23] arm64: ilp32: introduce ilp32-specific handlers for sigframe and ucontext
From: Zhangjian (Bamvor) <hidden>
Date: 2016-06-12 12:39:35
Also in:
linux-arm-kernel, linux-s390, lkml
Hi, Yury Here is another print issue in this patch: On 2016/5/24 8:04, Yury Norov wrote:
From: Andrew Pinski <redacted> ILP32 uses AARCH32 compat structures and syscall handlers for signals. But ILP32 struct rt_sigframe and ucontext differs from both LP64 and AARCH32. So some specific mechanism is needed to take care of it.
[...]
quoted hunk ↗ jump to hunk
diff --git a/arch/arm64/kernel/signal_ilp32.c b/arch/arm64/kernel/signal_ilp32.c new file mode 100644 index 0000000..841e8f8 --- /dev/null +++ b/arch/arm64/kernel/signal_ilp32.c@@ -0,0 +1,192 @@ +/*
[...]
+asmlinkage long ilp32_sys_rt_sigreturn(struct pt_regs *regs)
+{
+ struct ilp32_rt_sigframe __user *frame;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ /*
+ * Since we stacked the signal on a 128-bit boundary,
+ * then 'sp' should be word aligned here. If it's
+ * not, then the user is trying to mess with us.
+ */
+ if (regs->sp & 15)
+ goto badframe;
+
+ frame = (struct ilp32_rt_sigframe __user *)regs->sp;
+
+ if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
+ goto badframe;
+
+ if (restore_ilp32_sigframe(regs, &frame->sig))
+ goto badframe;
+
+ if (compat_restore_altstack(&frame->sig.uc.uc_stack))
+ goto badframe;
+
+ return regs->regs[0];
+
+badframe:
+ if (show_unhandled_signals)
+ pr_info_ratelimited("%s[%d]: bad frame in %s: pc=%08llx sp=%08llx\n",
+ current->comm, task_pid_nr(current), __func__,
+ regs->pc, regs->compat_sp);It should be sp instead of compat_sp. The latter one is used by aarch32 EE. Regards Bamvor
+ force_sig(SIGSEGV, current); + return 0; +} +